Process of matting textile materials



Patented Nov. 24, 1942 MATERIALS Albert Landolt, Riehen, and Hans Benz,Basel, Switzerland, assignors to the firm oi Society oi ChemicalIndustry in Basie, Basel, Switzerland No Drawing. Application September25, 1939, Se-

rial No. 296,525. In Switzerland September 30,

1 Claim.

In the specifications of U. S. Patent No. 2,145,- 011 and of applicationSerial'No. 271,392, filed May 2, 1939, there is described a process ofthatting textile materials, especially those consisting of regeneratedcellulose or cellulose esters or ethers by treating the material inamatting bath containing urea and formaldehyde or a sol ubleurea-formaldehyde compound, for instance mono or dimethylolurea. I

The process of the said specifications consists in adding to the mattingbath a condensing agent (acid) and by suitable choice of temperature,concentration and liquor. ratio, bringing about a precipitation of thecondensation product produced by the action of the condensing agent in apigment-like form on the fibre.

The present invention relates to the performance of the process in acontinuously operating or standing bath, that is'to say, that the bathis used repeatedly and the fresh reagents are olurea during 3 hours ofmatting operation and at a temperature of C. It is generallyadvantageous to operate the temperature below 40 C. advantageously atroom temperature, that is to sayat Ill- C. However matting proceeds bestat about 20 C. and requires a somewhat longer period at a higher orlower temperature v than this. a

If for any reason the matting process is to be interrupted, the mattingbath is brought to added to keep up'the concentration. The urea andformaldehyde or the water-soluble condensation product from urea andformaldehydeis added to the bath with the addition of so much acid thatthe bath has a feeble but pronounced reaction to Congo. Under suchconditions there is immediately formed in the bath a water-solutheessential factor to be considered is the hydrogen ion concentration. Thelatter may vary according to the concentration of the soluble ureacompound, namely the higher the concentration neutrality by an additionof alkali. When the matting is to be restarted the bath receives thenecessary proportion of acid before the operation begins.

The invention is applicable to both the dyed and undyed materials. Thedyeing may follow the matt ng operation. For producing a given mattingefl'ect the duration of the matting process. must be adjusted inaccordance with the various factors indicated above. 'Thus the user isable of the urea-formaldehyde compound, the lower permit. An' advantageof the invention however is that a long liquor ratio is commerciallypossible. Thus for instance the operation-may be performed with a liquorratio of 1:10, but it is of value as stated that the operation can beconducted at liquor ratios of at least 1:15 for exby increasing ordiminishing the concentrationof the matting agent or the acid or bylengthening or shortening the bath to accelerate or retard the mattingoperation.

The following examples illustrate the inven-- tion:

' Example 1 4 kilos of dimethylolurea are dissolved in litres of waterat 70 C. The liquor is then cooled to 20 C. and made up to 200 litres byaddition of water at the sanie temperature. 10 kilos of viscoseartificial .silk in hank form are reeled in this bath for 15 minutes andthere are then added 3.2 litres'of hydrochloric acid of 36 per centstrength. The artificial silk which has been thus treated for 2 hourshas agood matting for 2 hours.

fast to washing.

There is then added to the bath 1 kilo of dis solved dimethylolurea, 10kilos' of viscose artificial silk areentered and the reeling is repeatedThe material then shows a strong matting fast to washing. For furtherbatches of artificial silk to be matted the same addition ofdimethylolurea is made and if necessary further acid is added. a

have a strong matting effect.

Example 2 1 kilo of viscose artificial silk is reeled during 1 hour at20 C. in 80 litres of liquor containing 0.32 kilo of urea, 0.48 litre ofa formaldehyde solution containing 360 grams of formaldehyde per litreand 1.28 litres of hydrochloric acid of 36 per cent strength. Theartificial silk thus treated is strongly matted. For further matting inthe same bath the liquor receives 0.1 kilo of urea and 0.16 litre offormaldehyde solution, whereupon it is ready for similarly matting afurther l-kilo of the viscose artificial silk.

Example 3 10 kilos of viscose artificial silk tricot are matted at 20 C.in 100 litres of liquor containing per litre 10 grams ofmonomethylolurea and 10 cc. of hydrochloric acid of 36 per cent strengthAfter reeling for 1 hour the goods are rinsed and dried, whereupon theartificial silk is found to For the next batch of tricot there is addedto the liquor per litre 6 grams of monomethylolurea and 2 cc. of hydrochloric acid of 36 per cent strength. If instead of 10 grams ofmonomethylolurea per litre only grams are used, the matting effect isweaker.

Example 4 kilos of viscose artificial silk crepe are reeled at 20 C. in400 litres of liquor containing per litre 3.5 grams of monomethylolureaand 20cc. of hydrochloric acid of 36 per cent strength. After mattinghas continued for 1 hour the goods are rinsed, neutralized and dried,whereupon they-are found to have a matting of medium strength. Beforestarting to mat the next batch of viscose artificial silk crepe thereare added to the bath per litre 1.5 grams of monomethylolurea and 1 cc.of hydrochloric acid of 36 per cent strength and the operation isrenewed in the manner described above. If instead of 3.5 grams ofmonomethylolurea per litre there are used 5 grams of monomethylolurea astronger matting effect is obtained.

What we claim is:

In the process of matting textiles which comprises handling the textilesin a bath containing a member of the group consisting of (a) urea andformaldehyde and (b) a water-soluble ureaformaldehyde compound underconditions whereby a water-insoluble urea-formaldehyde condensation isformed and is adsorbed by the textiles to be matted, the steps ofrepeatedly adding fresh reagents to the treating bath as the oldreagents are consumed in order to maintain the proper concentrationthereof, and repeatedly subjecting fresh textiles to matting in thereplenished treating bath, the said bath having a liquor ratio of atleast 1: 15 and a hydrogen ion concentration corresponding to that of asolution of at least 2 cc. per liter of hydrochloric acid of 36 per centstrength.

ALBERT LANDOLT.

HANS BENZ.

